The researchers focused on three genes
Australian researchers have identified a significant link between a gene involved in testosterone action and male-to-female transsexualism.
DNA analysis from 112 male-to-female transsexual volunteers showed they were more likely to have a longer version of the androgen receptor gene.
The genetic difference may cause weaker testosterone signals, the team reported in Biological Psychiatry.
However, other genes are also likely to play a part, they stressed.
Increasingly, biological factors are being implicated in gender identity.
There is a social stigma that transsexualism is simply a lifestyle choice, however our findings support a biological basis of how gender identity develops.
– Professor Vincent Harley, researcher
